Node.js Cron Job Messing with Date Object - node.js

Question

I'm trying to schedule several cron jobs to generate serial numbers for different entities within my web app. However I am running into this problem, when I'm looping each table, it says it has something to do with date.js. I'm not doing anything with a date object ? Not at this stage anyway. A couple of guesses is that the cron object is doing a date thing in its code and is referencing date.js. I'm using date.js to get access to things like ISO date.
for (t in config.generatorTables) {
console.log("t = " + config.generatorTables[t] + "\n\n");
var ts3 = azure.createTableService();
var jobSerialNumbers = new cronJob({
//cronTime: '*/' + rndNumber + ' * * * * *',
cronTime: '*/1 * * * * *',
onTick: function () {
//console.log(new Date() + " calling topUpSerialNumbers \n\n");
manageSerialNumbers.topUpSerialNumbers(config.generatorTables[t], function () { });
},
start: false,
timeZone: "America/Los_Angeles"
});
ts3.createTableIfNotExists(config.generatorTables[t], function (error) {
if (error === null) {
var query = azure.TableQuery
.select()
.from(config.generatorTables[t])
.where('PartitionKey eq ?', '0')
ts3.queryEntities(query, function (error, serialNumberEntities) {
if (error === null && serialNumberEntities.length == 0) {
manageSerialNumbers.generateNewNumbers(config.maxNumber, config.serialNumberSize, config.generatorTables[t], function () {
jobSerialNumbers.start();
});
}
else jobSerialNumbers.start();
});
}
});
}
And this is the error message I'm getting when I examine the server.js.logs\0.txt file:
C:\node\w\WebRole1\public\javascripts\date.js:56
onsole.log('isDST'); return this.toString().match(/(E|C|M|P)(S|D)T/)[2] == "D"
^
TypeError: Cannot read property '2' of null
at Date.isDST (C:\node\w\WebRole1\public\javascripts\date.js:56:110)
at Date.getTimezone (C:\node\w\WebRole1\public\javascripts\date.js:56:228)
at Object._getNextDateFrom (C:\node\w\WebRole1\node_modules\cron\lib\cron.js:88:30)
at Object.sendAt (C:\node\w\WebRole1\node_modules\cron\lib\cron.js:51:17)
at Object.getTimeout (C:\node\w\WebRole1\node_modules\cron\lib\cron.js:58:30)
at Object.start (C:\node\w\WebRole1\node_modules\cron\lib\cron.js:279:33)
at C:\node\w\WebRole1\server.js:169:46
at Object.generateNewNumbers (C:\node\w\WebRole1\utils\manageSerialNumbers.js:106:5)
at C:\node\w\WebRole1\server.js:168:45
at C:\node\w\WebRole1\node_modules\azure\lib\services\table\tableservice.js:485:7
I am using this line in my database.js file:
require('../public/javascripts/date');
is that correct that I only have to do this once, because date.js is global? I.e. it has a bunch of prototypes (extensions) for the inbuilt date object.
Within manageSerialNumbers.js I am just doing a callback, their is no code executing as I've commented it all out, but still receiving this error.
Any help or advice would be appreciated.
Ok I've commented out the date.js module and now I'm getting this error:
You specified a Timezone but have not included the time module. Timezone functionality is disabled. Please install the time module to use Timezones in your application.
When I examine the cron.js module it has this statement at the top:
var CronDate = Date;
try {
CronDate = require("time").Date;
} catch(e) {
//no time module...leave CronDate alone. :)
}
So this would conclude then that it does have something to do with the date.js module ?
Anyone see whats wrong.
cheers

Answer 1

I was using date.js for a while, and then realized that the Date object in Node.js/V8 already had ISO support, input and output, and Date.js only added a very specific edge case. What exactly do you need date.js for?
If you do need date.js...
is that correct that I only have to do this once, because date.js is global?
That's true as long as the code is running in the same process. I'm not familiar Node.js on Azure, or the library providing the cronJob method you're using, but perhaps it spawns a new process, which has its own V8 instance, and then you lose the Date object changes? (So require it again in that code.)